AS A PART OF BUILDING FIRE PROTECTION
Summary Minutes of Seminar on May 3, 1977
U.S. DEPARTMENT OF COMMERCE
National Fire Prevention and Control Administration
Washington, D.C. 20230
NATIONAL FIRE PREVENTION AND CONTROL ADMINISTRATION'S
FEDERAL FACILITIES DESIGN STANDARDS TASK GROUP
RICHARD KLINKER (Chairman) JULES L. BIGIO
Central Office Headquarters
General Services Administration Consumer Product Safety Commission
FRANCIS BRANNIGAN EUGENE CARLSON, JR.
Headquarters Headquarters, Drug Enforcement Admin.
U. S. Department of Energy U. S. Department of Justice
WILLIAM L. HANBURY DWIGHT HULL
National Fire Prevention § Control Admin. Headquarters
U. S. Department of Commerce Tennessee Valley Authority
JAMES A. JOHNSON ABRAHAM M. KOOIMAN
Office of the Secretary Headquarters, OSHA/OFASP
U. S. Dept. of Health, Education, § Welfare U. S. Department of Labor
GEORGE MATSUMARA DONALD L. MOORE
Corps of Engineers Headquarters
U. S. Department of the Army U. S. Dept. of Housing § Urban Development
GEORGE W. MORGAN RICHARD A. RICE
Headquarters Chesapeake Division
National Aeronautics § Space Administration U. S. Department of the Navy
DIANNE WALTERS CHARLES L. WILLIS
Central Office Headquarters
General Services Administration Consumer Product Safety Commission
HIGHLIGHTS AND RECOMMENDATIONS OF THE NFPCA'S
FEDERAL FACILITIES DESIGN STANDARDS TASK GROUP
SEMINAR ON SMOKE CONTROL OF MAY 3, 1977
1. Highlights .
The following highlights are emphasized with no order of importance implied:
a. Test procedures have not been updated to reflect life safety hazards of modem man-made polymers,
plastics, and synthetics.
b. Firefighting by building occupants without self-contained breathing apparatus may be deadly.
c. Exposure to minute quantities of hydrogen chloride (HC1) in air can cause disabling choking and
burning sensation to eyes, nose, and throat. Polyvinylchloride releases approximately 58% of its
weight as hydrogen chloride in a fire.
d. There are a number of factors, other than the heat of the fire, which allow delivery of dangerous
quantities of smoke and toxic gases to locations remote from the fire regardless of design con-
siderations, e.g. inversion or lapse, external temperature, wind direction, and building
operations at the time of the fire.
e. When a building is heated, the difference between inside and outside temperature causes so-called
"stack ffect." Due to pressure differences, air is drawn into any ventilating stack (stairways,
elevator shafts, floor openings) in the lower part of the building. At about the mid-height of
the building, there is a neutral plane (zone) where air flow is indeterminate. Above the neutral
plane the flow of air is from the stacks to the floors. Gases from a fire below the neutral plane
will follow the existing air flow paths and be delivered to floors above the neutral plane. Many
variables affect the condition in a specific building. When a building is cooled below outside
temperatures the affect is reversed.
f . Tests on non-pressurized buildings indicate the following:
(1) Fire on a floor below the neutral plane can be spread into the corridor by airflow.
(2) Smoke from floors beneath the neutral plane can be spread to upper floors by the air handling
(3) Smoke on upper floors will be forced outside.
(4) Weather can have a significant effect on pressures.
g. Some tests have indicated that pressurization of corridors to reasonable levels on floors above
the neutral plane can contain a fire in its room of origin. The use of regular air handling
systems is practical for most cases of smoke control and minimizes costs .
h. Pressurization is considered a sound method of smoke control. Further evaluation may lead to
designs permitting the use of elevators by occupants for evacuation.
i. At present, there is a lack of complete understanding and knowledge in engineering smoke control
systems . It is more of an art than a science and adoption of legislation without additional
knowledge and experience can be counterproductive.
j . No one can actually state at this time for a given building precisely what amount of pressurizption
is required to achieve desired results . The only means of determining adequacy is by full-scale
testing with a trace gas, such as SFg.
k. Automatic smoke control mechanisms are subject to malfunction.
1. Wider use of smoke control systems is inhibited by potential liability considerations.
m. Research at the National Bureau of Standards and the Canadian Building and Research Council
indicates that six air changes per hour is the maximum needed for smoke control; however, a
ndnimum of three air changes may possibly be acceptable.
n. Smoke control requirements will virtually eliminate the need for fire dampers.
o. Based on locaL- research, Atlanta, Georgia has required that all high-rise buildings built since
1973 include pressurization systems for smoke control.
p. In order to achieve reliability in smoke control systems, a design manual is essential.
a. Federal agencies should utilize research funds to assist in the formulation of a smoke control
b. Existing data about smoke control systems must be transformed into charts, graphs, tables, and
formulae to include all parameters, such as wind, temperatures, building geometry, volume, and
other special features as a "state-of-the-art" basic reference.
c. In the design of new and rehabilitated buildings, smoke control should be seriously evaluated
for feasibility for inclusion.
d. Pre-fire planning for buildings containing smoke control systems should include contingency plans
for the various stack-effects which may occur in the building at various times (e.g. various
seasons of the year) and the need for self-contained breathing apparatus for building occupants.
January 24, 1978
Highlights and Recommendations by the NFPCA's
Federal Facilities Design Standards Task Group i
Summary Minutes of Seminar ...... 1
Richard Klinker, General Services Administration
Robert Taylor, Republic Steel
INTRODUCTION TO SMOKE CONTROL ... 1
Richard Masters, Jaros, Baum & Bolles, Consulting Engrs.
SMOKE CONTROL METHODOLOGY AS IT RELATES TO
THE DESIGN PROFESSION .... 3
Francis Fung, National Bureau of Standards
SMOKE CONTROL CONCEPTS OF DIFFERENT COUNTRIES . 4
Brooks Semple, Fire Prevention Consultant
SOME PITFALLS OF MODERN DESIGN AND MATERIALS . 6
William Schmidt, Veterans Administration
DESIGN NEEDS OF AIR CONDITIONING CODE, NFPA 90A 7
Robert Taylor, Republic Steel
THE FUTURE: ASHRAE SMOKE CONTROL DESIGN MANUAL 7
QUESTIONS AND ANSWERS 8
MR. KLINKER: The Task Group on Federal Facilities
Design Standards is open to all Federal agencies.
The Task Group is set up to develop standards and
guidelines for fire protection and fire prevention
relating to buildings, structures and facilities.
The areas of concern are occupancy and fire pro-
tection systems and equipment for assuring ade-
quate consideration for life safety, continuity
of operations and property protection.
The Task Group will assist in reviewing plans for
new constructions, make independent studies of
Federal buildings and property and consult with
appropriate organizations. Thus the Task Group
serves as a focal point for the various govern-
ment agencies to learn what other agencies are
MR. TAYLOR: The concept of the use of air for
smoke and fire control is at a stage where sound
design criteria must be available to architects,
engineers, the fire profession, building code
officials and others who have jurisdiction over
the construction, maintenance and control of
Participants in the meeting include Dick Masters
of Jaros, Baum & Bolles. Mr. Masters is chairman
of the Subcommittee on Control of Fire and Smoke.
Bill Schmidt of the Veterans Administration is the
current chairman of the NFPA 9QA Conmittee.
Francis Fung represents the National Bureau of
Standards Fire Technology and Record Section. He
is chairman of the Handbook Subcommittee . Brooks
Semple is Executive Director of the Smoke Control
Association and secretary of the NFPA 9CA Com-
mittee. John Fothergill is the last speaker.
Discussion followed on the National Disaster
Survival show on network TV. It was felt that the
show depicted several myths on life and fire
safety which should be rectified. The National
Safety Council will be asked to carry another TV
special program to properly set the record straight.
The residence fire and high-rise procedures were
Mr. Taylor then began a slide presentation on
smoke and toxic fire gases. When a fire occurs
the code mandates that the air system be turned
off thus creating a "witches brew" of smoke and
toxic fire gases from cellulosic products.
The chance of survival in many buildings is jeo-
pardized by test procedures which have not caught
up with the real life-safety hazards of many
modem materials. Construction practices, too,
often compound the problem of exit from and access
to buildings and make smoke control and fire con-
trol difficult at best.
Building air systems and certain hazard control
techniques can dramatically reduce both life and
The entire fire technology of the recent era was
based on control of the "wood" fire. During this
period so-called "fireproof" building construction
came into being. Codes were aimed basically at
protecting the integrity of the structure from
fire. After numerous disasters, life- safety codes
grew in importance and use.
Firefighting concentrated on putting out the fire.
It was the age of the "smoke-eater" with smoke from
cellulosic materials. Even though wood smoke is
very high in the release of aldehydes and carbon
monoxide, few considered toxic gases.
The concept of "fire load" was born to judge the
degree of fire hazard of a building. This meant
the fire endurance of a structure was based on the
pounds of combustible materials in its construc-
tion and contents.
The ASTM E-119 test was developed and the E-119
typical fire curve is still used to determine the
degree of fire resistance and performance of a
system or material.
There is a new technology of man-made polymers ,
plastics and synthetics. These polymers are com-
pletely burned in less than five minutes, and the
rate-of-smoke development is very great. Toxic
hazards of the fire gases and flame spread can be
so great that so-called "first aid" firefighting
without self-contained breathing apparatus may be
The Ohio State Combustibility Test Method was
reviewed. This test still uses wood as the material
to evaluate the hazard of a fuel load.
The Federal Trade Commission has ruled that many
of the test methods and standards adapted to
cellular plastics are "not accurate indicators of
the performance of such materials under actual
Further, the E-39, Hazards of Materials Committee
of ASTM, is reviewing all Fire Hazard Test Methods
and Standards for their relevancy under actual fire
PVC, for instance, releases approximately 58 percent
of its weight as HCL or hydrogen chloride. Less
than 200 parts per million of this gas combined
with other gases when it decomposes can "arrest"
an exposed person. The combined effect of these
gases on an individual in a fire situation will
depend on the amount of material involved, the rate
at which gases are released, the size of space into
which they are released, available oxygen, and the
ability to evacuate the area.
Research is being done at the University of Pitts-
burgh which indicates that more potent sensory
irritants than HCL may be involved. In a report
presented at the International Symposium of
Toxicity and Physiology of Combustion Products,
it was revealed that HCL has been implicated as a
major contributor to the overall toxicity exhi-
bited by the thermal decomposition products of
The University of Pittsburgh work also indicates
no difference in the degree of severity of the
respiratory effects suffered from the thermal
decomposition products of plasticized (PCV) as
long as oxygen was above 14 percent, carbon diox-
ide below 10 percent and carbon monoxide less than
This data indicates that exposure to 0.10 to 0.22
milligrams per liter of air of HCL would be
rapidly incapacitating with choking and burning
sensation of the eyes, nose and throat. It also
shows quite clearly that HCL alone is not the
sole incapacitating agent.
Empirical gas concentration data and tests indi-
cate that one pound of PVC, when burned, can
release concentrations of HCL of 200 ppm into a
corridor 10x10x50. Thus, a very small fire in-
volving small surface areas of PVC could have
large potential hazardous consequences to people
moving in such a corridor.
Likewise, Fire Hazard Characteristic 3, "Smoke,"
carries many ramifications. Is it dark or clear,
light or heavy, hot or cold, filling the entire
area floor to ceiling or stratified?
Although gases and many early products of com-
bustion are colorless, they are components of
smoke. Most test standards, however, are written
based on visible smoke, not invisible gases. The
rate at which smoke is given off by a given piece
of material is important and determines hazardous-
The scope of the hazard has been changed with the
high-rise construction and enormous growth in
vast area structures. Through design and con-
struction practices, firefighting is complicated
in many ways.
Exterior factors which seriously hamper fire-
fighting include (1) exterior landscaping which
makes emergency approach difficult; (2) light
construction parking ramps prevent apparatus from
reaching buildings; (3) turns which are too
narrow for fire apparatus approach; (4) fire
hydrant placement too far away.
There is a great need for careful, detailed
planning of a structure and its surroundings at
the design stage concerning basic fire detection
and smoke and fire gas control procedures, alert-
ing and evacuation programs, and careful plans
on fighting the fire from the inside.
The National Research Council of Canada has
determined that total evacuation is not practical
from any building over 30 stories in a reasonable
period of time. Even in a 20-story building, it
takes up to 20 minutes to evacuate people in
Codes still regulate the service materials and
exterior finishes for corridors based on fire
tests not applicable to modem materials. The
spread of fire can be dramatically reduced by
requiring all corridor materials to be noncombustible .
The carpet should meet the new criteria for fire
safety established by the National Bureau of Stan-
dards using a radiant heat test tunnel.
There is another myth that if a building is
sprinklered, combustible materials may be used
safely and the corridor length extended beyond 100
feet between exits. Unfortunately, with modern
polymers, the smoke load and flame travel rate may
be so great and move so rapidly before the sprinklers
operate that a corridor quickly can become non-usable.
Regarding school fire drills, school corriders
and classrooms, even though nonconbustible ,
have proved to be hazardous in fire experience
where basically wood is involved.
Next is the elevator. The message everywhere is
"do not use it in case of fire." Elevators by law
in many areas return to the ground floor.
The problem of why smoke goes up an elevator shaft
should be analyzed by those writing the laws. It
has been shown by work from Brown University and
the National Bureau of Standards that smoke will
move up to 50 feet per minute for the first three
minutes of a fire, and then up to 100 feet per
Vertically, that is 10 stories a minute. The smoke
can be stopped by closing the flue at the top of the
elevator. Again, an understanding of the aero-
dynamics of heat flow in a building can solve many
of the problems.
The vent at the top of an elevator shaft is a major
factor in permitting many working fires to quickly
involve an entire building.
Design points which deserve consideration include
non- fire-stopped shafts, locked exit doors, com-
bustible ductwork, combustible coatings, combustible
plumbing materials, etc.
Attempts are being made to control construction and
contents with test procedures which often bear little
relationship to how they burn in a real fire. Little
has been done to control quantity and rate of smoke
and gas release of materials. The subject of fire
technology is not taught in most architectural and
structural engineering schools. Fire spread should
be included in the fire reporting.
Many colleges and universities are now developing
courses on fire technology. Standards groups are
evaluating relevant hazards and tests for them.
The American Society of Heating, Refrigerating and
Air Conditioning Engineers is developing a new con-
cept of using air under pressure to reduce the real
potentials of a high-rise towering inferno. This
use of air for smoke and fire control is not yet
an exact science, but the record so far is impressive.
There is a "neutral point" usually near the middle
of the building where air pressures are static or
"neutral." Below this point, fire gases in non-
pressurized buildings move into the building.
Above the "neutral zone" smoke and fixe gases
In July 1972 a number of room burnout fire tests
were conducted at the Henry Grady Hotel in Atlanta
to determine the effectiveness of stairwell pres-
surization and the performance of certain
materials under fire conditions in "low hazard"
occupancies. The details of these fire tests were
discussed by Mr. Taylor. The results of these
tests are available in booklet form from Norman
Koplon, Architectural Engineer for the City of
The fact that pressurization works was proven in
an actual fire on March 7 , 1974, at the Carlyle
Apartment in Lakewood, Ohio. This apartment had
corridor pressurization. Everyone evacuated
safely and the fire was blackened down 15 minutes
after the alarm was sounded.
Unusual was the tightness of the corridor and the
almost complete burnout of the suite in which the
fire occurred with almost no conmunication to the
The data gathered from this fire tends to confirm
work done by the Canadian Building Research
Council, the National Bureau of Standards and
others. It shows: (1) fire oh a lower floor
below the neutral plane can be spread into a
corridor by the airflow; (2) smoke from floors
below the neutral plane can be spread to upper
floors by entrainment into the supply air system
if the system is not balanced to provide a posi-
tive supply to all floors under all conditions;
(3) fire on upper floors can be contained in the
fire room of origin by the airflow from a posi-
tively pressurized corridor; (4) smoke on upper
floors will be forced outside; (5) weather can
have significant effects on the pressures in the
From the study of the Carlyle it would appear that:
(1) Positive pressurized corridors using a "make-
up" air system can contain a fire within a suite
if: (a) the system is properly balanced, or (b)
the fire occurred in a suite above the neutral
plane. (2) With pressurized corridors the follow-
ing are essential: (a) stairwells should be pres-
surized more than corridors to keep smoke and
fire gases out of stairwells and vents at the top
of the elevator shafts should be closed; (b) non-
combustible corridor construction, including doors,
door frames, door hardware, acoustical ceilings,
wall coverings and service and conmunications con-
duit and pipe are critical since radiant heat is a
factor despite pressurization; (c) corridor
exhaust systems should be of a non-combustible
material; (d) suite exhaust systems should be non-
combustible; (e) all corridor doors should have
automatic self -closers ; and (f) each fire compart-
ment should have exterior windows or vents.
Positive air supply at approximately 0.10 inches
of water pressure kept this fire out of the corri-
dor even though the door had failed. Requirements
for 0.15 inches of water pressure appear excessive
in condomrniun- apartment type buildings.
Since that fire, there have been others where corri-
dor pressurization has worked. Pressurization does
work, sometimes even without an air system as
illustrated by a fire in Dallas, Texas.
The question was raised as to whether or not air
conditioning systems in high-rise office buildings
take off early fire gases to the point where fires
have a hard time developing.
Pressurization is a sound firefighting tool. With
it fire m en can get to the scene and fight a fire.
If life-safety is truly our concern, then smoke
detection, early voice alerting and pressurization
are the keys to future life-safety from developing
fires in fire-rated structures.
Much has been learned about flashover and the need
for full-scale room burning. But smoke and toxic
fire gases in the early stages outside the immediate
fire area are most critical to human life.
Through pressurization the elevators can be protected
and used to move people sensibly. We urge your support
on the design use of air systems for life-safety
and property control in buildings.
MR. MASTERS: Problems which the design engineer
faces today are numerous. There is a lack of complete
understanding and knowledge of methodology in engineer-
ing smoke control systems.
The kind of problem that design professionals are
confronted with is illustrated by a statement from
the latest NFPA 101 Standard— a life-safety code
which many use in design. "Access corridors in
buildings seven or more stories in height shall be
continuously pressurized to a minimum of .01 inches
on any unit door."
Conspicuously absent from this particular statement
is any limitation on the maximum pressure that may
be developed. If one is designing to a minimum,
then there must be some factor put into the design
to make certain that that minimum value is always
In bfessachusetts, as it relates to the amount of
air and the amount of pressure that has to be
maintained in stairwells, the same .01 number
appears in the latest Conmonwealth of Massachusetts
Code relating to air pressurization, and requires
that no less than 60 air changes be provided,
regardless of building height or configuration of
Further, it requires that all air be introduced at
the bottom, regardless of building height. With
those stipulated code requirements, it may be
possible to generate a situation which, although
consistent with the code, could be more dangerous
than the absence of a pressurization system.
This points to panic legislation written by people
who are properly motivated but without the tools to
either understand or solve the problem.
The situation exists where people writing the
legislation do not have the benefit of proper
backup advice and information relative to limi-
tations of equipment, dynamics of the forces
created, fan controls, etc.
There is a need for some good basic research.
Good work has been done under the auspices of the
National Bureau of Standards, through private
practitioners, various municipal agencies, state
agencies and Canada.
Technology has been developed to a point where,
given a smoke control design task and unlimited
funds and time, a workable solution could be
developed for a particular building which relates
to pressurization and smoke removal.
However, society is economically oriented and
people are held personally accountable for their
actions. The rigors of professional liability
preclude the undertaking of a design task for
which there is potential danger to life and the
acceptance of questionable codes.
No one can actually state for a given building,
for a given size and elevation, precisely what
amount of air will accomplish the desired result.
If a stairway pressurization has to function
under all conditions of usage, it must function
and maintain safe pressures when doors are closed
and when they are open. It does no good to
design a system which maintains safe pressures
only when the doors are closed. Similarly, an
excessively pressurized stairway will deny access
to it, and the solution becomes self-defeating.
An objective should be to develop a simple,
reliable system that has none or limited automatic
control. Automatic controls are subject to mal-
function and should be reduced to an absolute
minimum in a life-safety system.
The emphasis of methodology of control in smoke
control systems has to be looked at quite differ-
ently. One approach to excess pressure relief
might be in relieving excess pressure in a stair-
way by a simple barometric drafting. While this
arrangement might violate the fire resistant
integrity of the stair enclosure, a fire damper
could be added.
A one and one-half hour fireproof, self-closing
door in stairways is permitted. When the door is
open, there is no fire integrity. New thinking
has to be responsive to the design problem in
order to relate to relative risks.
New research is designed to get into the range of
dynamic systems by fighting fire with the use of
air systems. A clear definition of the problem
and an indicated solution must be in the design
manuals. Engineers need information they can
work with and information that is proven and
reliable enough to insure workable design. That
is what this program is all about.
MR. TAYLOR: Work done at NBS and the Canadian
Building and Research Council indicates that six
air changes per hour is the maximum that is needed.
It may be possible by good design to get down to
three or four air changes per hour. Then use of
the regular air conditioning system is practical
almost everywhere for smoke control.
Francis Fung will next speak on smoke control con-
cepts of different countries.
MR. FUNG: This slide depicts a smoke situation
down a 30-foot corridor with both ceiling and walls
lined with gypsumboard. The carpet is the only
combustible. The four wood cribs to the end of the
corridor were the only combustibles being ignited.
Due to the heat generated from the burn room and
subsequent heat transfer to the acrylic carpet, in
only five minutes smoke billows out from the corridor.
This burning will continue until the carpet is com-
In a high-rise building, aided by stacking and
buoyancy, smoke billowing out from a short corridor
will infiltrate the rest of the building.
The vertical scale indicates the height of the build-
ing in feet, and the middle point is the neutral plane.
The different intensity of the pressure is indicated
by a relative scale, assuming that the room tempera-
ture is 70 degrees . A maximum pressure difference of
.5 inches may be expected.
The passage of smoke can be devastating in terms
of life-taking potential, property damage and its
obstruction to firefighting.
In order to evaluate the effectiveness of smoke
systems, a trace gas technique experimental metho-
dology was developed. This involves the setting up
of a burn room with warm and pressurized air. This
pressurized air will simulate smoke from a burn room.
Infiltration of SF6 tracer gas carried by the smoke
will be sampled quantitatively to obtain a smoke
The effectiveness of any given smoke control system
is compared with the building in normal operations.
The Seattle Federal Building has a zoned systematic
pressurized system for smoke control. The concept is
that the building can be divided into seven zones,
and given a fire situation, the fire zone in three
floors will be exhausted. Immediately above and
below will be pressurized to keep the smoke from
moving away and infiltrating the rest of the building.
The stack effect in a stairwell will move smoke which
is positive at the bottom and negative on the neutral
plane with respect to the floor. The pressures are
such in a sheltered interior stairwell that there
will be less pressure differences than the maximum
predicted. This is a desirable situation. It means
in smoke control the building can be designed to
counter interior stairwell pressure differences
rather than maximum external differences.
In a simulated smoke control mode where the middle
zone around the 20th floor is exhausted and the floors
above and below are under pressurization, the smoke
control mode was able to overwhelm the normal pro-
file and have a pressure profile which will prevent
the smoke at the middle zone from moving up and below
the fire zone.
The San Diego VA Hospital is an interesting build-
ing with four individual wings, connected by corri-
dors to a central core. The elevator shafts are
in the central core. Each floor and wing have
individual HVAC systems which can be controlled
Experiments were performed with this building,
simulating a horizontal smoke control mode. When
smoke was simulated in the south wing, pressuri-
zation was exhausted and the west, north and east
wings were pressurized to keep the smoke from
moving away from the south wing. In a pressure
measurement, smoke control mode was achieved.
When there was smoke control there was no measur-
able smoke infiltration of the building except in
the fire wing itself.
Various smoke control ideas being applied overseas
in shopping malls are not included in the experi-
ments from abroad; only those from average type
A Canadian experiment recommends that all fire
areas be pressurized and that the fire floor be
provided with a means of venting to outdoors by
smoke shafts or windows. Another suggestion was
the pressurization of the central core in a high-
rise building. One other smoke control idea might
be, in the case of two separate buildings con-
nected by a bridge on each floor, to separate the
two buildings to prevent fire from spreading
from one wing to the other.
The French emphasis is to supply air from the
bottom of the corridor floor and to pick it up
from the ceiling of the corridor. It is hoped
that stratification exists so that smoke gets to
the top and cool air is supplied on the bottom
for safe exiting.
A smoke control method which the British are
using consists of distributing air supply into
the stairwell and thus developing a pressure
throughout the stairwell of 58 Newton per meter
square. The fire floor is vented to the outside;
thus there is a need to exhaust or evacuate the
hot combustible airs and smokes from the source.
Incidentally, smoke is not only toxic by itself;
it also obstructs firefighting and is also com-
bustible. When a sufficient amount of this com-
bustible is accumulated in any wide-open area,
with the right temperature, flashover occurs.
It is advisable to exhaust as much of the unbumed
combustibles from a fire as you can.
It is the recommended practice in firefighting to
vent combustible mixtures to avoid a flashover.
To calculate the force on a door of 20 square
feet, take 50 times the pressure difference in
terms of inch of water. Only a .2 inch pressure
maximum can be permitted. In general, in a fire,
the pressure attenuates very quickly away from
the fire. Generally accepted opinion is that
the energy from the system can overcome the
pressure of a fire except in the immediate vici-
nity of a large fire. Away from the fire the sys-
tem can develop sufficient pressure to control
Smoke control by proper application of HVAC systems
as a life-safety feature in a large modern structure
is here today. Many experts around the world strongly
recomnend it and practice it. However, the various
smoke control approaches are lacking systematic and
optimization studies and guidelines.
The architect does not know what smoke control con-
cepts are available and which is appropriate for
his building for the level of protection needed.
The designer does not have the ready tools to
transform the concept to HVAC requirements for a
A systematic and comprehensive study of available
concepts is needed. Next, a matrix of design guide-
lines for proper selection of smoke control concepts
for a given building is required. Finally, optimi-
zation and design studies have to be performed by
application of theoretical analysis, large and small
scale experiments and computer studies.
This comprehensive study has to be transformed into
a volume containing charts, graphs, tables and
formulas — the tools a designer is accustomed to using.
External effects such as the wind and temperature
differences have to be included. In addition, building
characteristics — in terms of geometry, volume and
special features — have to be considered.
The manual also should incorporate codes and standards
that have been enacted on pressure and flow require-
ments for a specific smoke control.
This smoke control design manual for engineers is a
monumental and costly task, but the art of smoke
control needs this manual for the propagation of
its cause. Without this comprehensive design tool,
the progress of smoke control will continue to move
in an aimless manner. In the end, whatever spark
or brilliant smoke control ideas that come along
will remain in the hands of a selected few without
achieving the full benefit of saving lives.
MR. TAYLOR: We do not have all the answers on
pressurization systems. We do know, however, that
a smoke control system can be designed quite accurately.
But until the structure is erected and actually tested,
it is difficult to predict exactly how well it will
work. This is an area where improvement is needed.
Smoke control systems are not expensive. Quite the
contrary. If smoke control design is part of the
building systems package, the problems and programming
of the automatic switching of systems can be accom-
plished off the basic control equipment.
The problem of wind was one of the design parameters.
The wind is no problem until the building loses its
Smoke control systems can be practical and reasonable
in cost. Available to you today is a tentative research
project report, TKP 206.
No one system is going to solve all the problems.
Early warning detection is still needed as well as
training of staff. The protective systems already
in use should be continued. Smoke control is just
one major new tool which will reduce the potential
of a fire moving out of the area of origin.
Brooks Semple will next present a discussion of
pitfalls of modern design and materials.
MR. SEMPLE: A very common fire start is one with
a clean flame, plenty of oxygen and not much
smoke. This is the way a fire started in an
automatic transmission plant in Livonia, Michigan.
This particular fire rewrote the codes for indus-
Livonia, Michigan, had a number of acres under
one roof. A residential bedroom is approximately
200 square feet. That gathering of smoke at the
ceiling stops at the side walls and has no place
to go but down.
The Livonia, Michigan, fire did not get to the
stage where the air became contaminated and
people had to be evacuated. Personnel safety is
not a major problem in one-story plants, no matter
how many acres they are .
Those areas where fire protection engineers have
been applying their talents are those areas where
dollars were protected, not lives.
The first five minutes of a fire are more impor-
tant than the next five hours.
As stated earlier, the Henry Grady fire helped
establish the use of pressurization for smoke con-
trol. The Atlanta motel test fire further tested
pressurization, but it was mainly a test of in-
expensive sprinkler systems for bedrooms.
The furnishings in the Henry Grady were less than
normal. There were no draperies nor combustibles
on the walls or ceiling — only a carpet pad, one
bed, no overstuffed chair and no papers strewn
about. This bedroom was furnished more sparsely
than your own.
In 3 minutes and 40 seconds, the flame became
self -extinguishing because the door was closed.
There is no need to furnish hotel rooms with
sprinklers. The fires will be self -extinguishing
as long as the doors remain closed. The people
inside will be self -extinguishing too. This is
the new problem we have.
Built-in extinguishing systems have done a tre-
mendous job in holding down insurance premiums
because of the reduction of loss and incidents of
substantial loss where great masses of property
are assembled under a single roof.
When the motel bedroom door was left closed, the
fire room was vented in 17 minutes following
self -extinguishment . The fire was reignited,
and after 18 more minutes the sprinkler opened.
At that point the fire was no longer visible
because of the heavy smoke.
At the moment of opening the door, there was little
fire pressure pushing the smoke out. In another
minute the airflow switched around to a natural
draft. Because fresh air is flowing into the fire
room, it is clean for the first three feet of
elevation. Fresh air feeds the fire. It develops
the fire so that heat builds up and the sprinkler
head opens. The fire would never have left that
room of origin and catastrophe would have been
averted. Sprinkler systems are still the best way
of averting catastrophe. No where in recorded
history have 12 or more people been lost in a
Fusible link manufacturers are given a latitude of
10 degrees Fahrenheit plus or minus five. A fusible
link must open between 160 and 170 degrees Fahrenheit
in water . However , the ' 'UL Standard 33 , Standard For
Fusible Links" which is also used for fusible links
on sprinkler heads, allows an ordinary range fusible
link (from 125 to 170 degrees Fahrenheit) which need
not open until 290 degrees Fahrenheit.
On UL's particular time temperature curve, 290 degrees
Fahrenheit occurs in six and one half minutes. The
fire may push faster and hotter than that.
A therma-couple was mounted on the link in the test
bedroom. The ceiling temperature never exceeded 225
degrees Fahrenheit until the door was opened. This
is why the 165-degree links do not open. Thus we
cannot depend on any heat-sensitive device, as now
widely marketed, for life safety in the room of fire
Smoke control depends on smoke detection. Thermal
devices are too slow.
Crib bums are familiar to everyone in the fire pro-
fession. A crib bum was conducted in Sacramento
four years ago. A small five-room frame house was
used. The walls were plaster and the wallpaper had
peeled off. There was no paint on the wall.
The only combustible part of the house that could
have been exposed to any fire internally was the
window and door frames and the carpet padding in the
Because the living room was the largest room in the
house, it was used for the test. The idea was to
test the difference between materials commonly used
in a home a generation ago and those used today.
Twelve minutes from ignition was self -extinguishing .
If the infant had been on the floor, it would have
Today we are in a plastic era. There has been a
tremendous growth in the use of plastic furnishing.
In the fire test of the foam mattress and common
plastic covering on the crib, both cribs were
identical at 30 seconds into the fire. After that
period the identity ceases. Flashover occured at
three and one half minutes.
We have a substantial problem and need help.
MR. TAYLOR: A smoke detector, UL labeled, should
be properly installed in all residences. Secondly,
be certain that the label is not a ULC label. That
only identifies conditional certification. Those
in a position to do so should urge legislation and
code action. Legislation should be enacted to
require smoke detectors in all new buildings as
well as existing structures.
This new plastic era is here. The wood era is fading.
In a plastic era, the same time limits do not
exist. The toxicity is nuch even in a beginning
fire, that unless easy access is available, the
fire department should fight the fire. The fire
department should also be aware of toxic gas haz-
ards. Even though the fire might seem a clear
one, gases cannot be seen and masks should be
worn. It is the clearest smoke which is the worst
and that occurs in the early stages of fire.
Bill Schmidt of the Veterans Administration will
next speak on the design needs of NFPA 90A, the
Air Conditioning Code.
MR. SCHMIDT: The NFPA standards are widely used,
either directly as in the private sector, or
through various Agency requirements in the Govern-
Years ago the installation of fire dampers in
ducts was the way building fire safety was
designed. About three years ago Appendix B was
added to the code to permit the systems to be
used as smoke control systems.
However, because of the increased awareness of
smoke and toxic gas danger, much has been done.
Most of the progress has been in the life-safety
One section of the code requires that in a build-
ing with seven or more stories, the corridor be
continuously pressurized to a minimum of .01
inches at every living unit door. This means that
the air conditioning and ventilation systems are
The 90A code states that the corridor cannot be
used as a portion of a supply or return air plenum.
This presents a conflict to the designer.
The 101 approach is the right way to go.
Section 9 concerns shopping malls. It requires
that a covered mall shall be provided with smoke
control in accordance with 12-37.
Perhaps the most important section concerns the
use of smoke dampers and fire dampers in parti-
tions. Openings in fire partitions for air duct-
work or air movement shall be protected with fire
dampers. This requirement need not apply, and
this is the exception, for ductwork is part
of an engineered smoke control system. Smoke
control has almost eliminated the need for fire
The 90A conmittee has discussed the use of duct-
work, sprinklers and dampers. 101 has taken fire
dampers out, which is quite substantial.
The seriousness of smoke control systems is reflec-
ted in the life safety code. There is willing-
ness to trade off fire and smoke dampers to obtain
a good smoke control system.
ASHRAE has done a great deal. In addition, there
is available within the Society reports on build-
ings which have been built, smoke tested, re-
designed and retested.
One of the most important activities in ASHRAE is
to get material into print and get it referenced
for use by designers. There is also the insurance
and professional liability which have to be con-
sidered. The consensus method must stand up in
court to protect everyone.
The NFPA is endeavoring to get as much as possible
into Appendix B. The building air conditioning
systems that have been designed and installed for
normal cooling will be used. This has been found
to be more than adequate in most cases to do the
MR. TAYLOR: Many people still Question how much of
the above is an experiment and how much is proven.
In Atlanta, every high-rise erected during the past
four years has had different types of pressurization
systems designed into it.
There have been no fires which have gone beyond the
incident stage in these pressurized buildings in
the past three years.
In some of the local governments there has been cost-
cutting which has forced fire departments and building
departments into a position of insufficient manpower
to properly design building fire safety and conduct
fire prevention inspections along with their fire
It will take a national effort to educate local
officials and the American public that more
critical than the firefighting may be the building
review initially and the need for continued inspec-
tions by both building and fire departments.
The irony of fire suppression is that by putting out
the fires and having a low loss record, the city
councils then cut into the fire departments' budget
and manpower. This portends a tragedy.
The air conditioning systems can be used to control
smoke in the early stages of a fire. The codes should
be changed to permit the air systems to remain on
until they are automatically reconfigured to a smoke
control mode. As long as fresh air is circulating,
the problems of panic in a fire are dramatically
The Squibb Building in New York was a case in point.
The air systems were turned off and 1,600 people on
upper floors panicked. Windows were smashed. When
the air systems were turned back on, the level of
panic in the area dramatically lessened.
Currently designers do not have a coherent pressuri-
zation design criteria to work with, as is available
in almost all other engineering disciplines. In
addition, designs are based on individual philosophy
and limited data. There is a need to go in after
construction and retrotest to be certain that what
was done was correct. Design guidelines need to
be printed. Finally, there is the liability which
exists from unproven tecliniques .
The actual design technology available is extensive.
Many of the techniques have been proved and tested.
However, the technology has not been catalogued for
what is needed; yet an effective design system is
dependent upon the structure that it is going into
and the HVAC system. Critical to this is the HVC
system and structural leakage.
What can be done in existing buildings where retro-
fit cannot be accomplished? Pressurized elevator
shafts may be one way to stop stack effect in the
building and create a staging area for firemen. A
further concept is to then put a fan on the car
itself to pressurize the lobby area.
I challenge the concept of taking the elevator car
out of service during the first three to five
minutes after an alarm has sounded. There is no
record of any individual having been injured or
dying in an elevator in a high-rise building in
recent years, other than after the HVAC systan
is turned off.
Smoke control should be tied into the air systems.
The system must be economical and effective.
There is a 10-story hospital which is now divided
into 30 different smoke zones. People in all but
three or four of the zones never even know when a
fire call comes in. This is developing real life-
Coherent design guidelines can be developed. Limi-
ted initial effort is underway at the National
Bureau of Standards, but it must be expanded.
All existing criteria should be put together in
one consensus and the existing experimental work
extended to all significant structural designs.
This means expanding the National Bureau of Stan-
dards' work to provide design guidelines for all
types of structures. This design guide will pro-
vide the necessary tools needed by engineers,
architects and building and fire officials to
judge the validity of the system and to smoke-test
ASHRAE will endeavor to provide a coherent design
basis in the form of a manual, as a part of the
ASHRAE Handbook. The manual will provide an
effective and rapid dissemination of design tech-
QUESTION: Where are the sources of information
now for this type of design? Does ASHRAE have a
good source list for designing of smoke control
MR. TAYLOR: ASHRAE has a supply of materials
available on this subject. NBS also has material
available on sources. Certain Canadian papers are
available. However, the data available today is
fragmentary, and it is difficult for designers and
architects to pull it out.
MR. FUNG: The data available at this point is
basically of a research nature. It is not design
information in a usable form. There is still much
work to be done to pool the resources and write
the design formulas, charts and tables.
Research is the first step toward technology. But
there is a great deal that has to be done to trans-
form this technology into design tools.
MR. SCHMIDT: The February 1976 issue of the ASHRAE
Journal was a special fire safety issue. The most
extensive reference that was available was included
in the articles.
QUESTION: Has the engineering problem of laboratory
buildings where there are multiple hoods with a lot
of ventilation for toxic materials been addressed?
MR. FUNG: There are computer programs which will
simulate this type of building. There are experi-
ments, comparative programs, small and large scale
studies which can simulate a building with these
specific problems. It is costly to run this program
and the tools are not available to everyone. Still
needed are charts and formulas to check against each
MR. SCHMIDT: Actually in laboratory buildings with
hoods there is a built-in ready exhaust system.
Let the hoods run. A hood fume will probably deter-
mine the amount of airflow. The smoke control system
must have both supply and exhaust.
MR. FOTHERGILL: The NTH Clinical Center will be
tested in June and should give some experimental
data in what is necessary when materials of this
sort use hoods to maintain evacuation of toxic
QUESTION: How can copies of experimental data be
MR. FOTHERGILL: The best source to contact is
Francis Fung of the Center for Fire Research at the
National Bureau of Standards.
MR. FUNG: ASHRAE and NRC of Canada are the other
two sources for additional information.
QUESTION: What effect will energy conservation
have on smoke control, such as opening windows
instead of having fixed windows. Does this affect
the firef ighting operation?
MR. SCHMIDT: The window problem actually in this
GSA building is one type of corridor. Most buildings
are block-buster type with a perimeter of rooms and
an interior core.
QUESTION: I was referring to the effect it would
have on the smoke control system.
MR. SCHMIDT: The firefighters know whether or not
they are above or below the neutral plane. An open
window at the wrong place could either save or kill.
The entire concept of energy conservation, the load
shedding of fans at any particular time of day, adds
an additional complication. Fortunately, most of the
systems for buildings are now being designed for
The computerized control system is becoming more
popular. All the systems are brought in electroni-
cally with computer surveillance.
In new buildings the cost factor may be inconsequential.
So, in some ways the energy conservation has helped.
VOICE: Do you perceive a trend to go to an HVAC
smoke control option or elimination of the damper?
Or do you see some combination of the two?
MR. SCHMIDT: There will be a caoibination of the
two because a physical barrier is needed.
MR. POTHERGTLL: Pressurization is only one tech-
nuqie. Compartmentalization is a very signifi-
cant and economical technique. It is closely
related to both fire protection and energy conser-
vation. Even a small compartnientalization scheme
helps in the smoke control area.
QUESTION: There are many kinds of combustibles
in areas of these high-rise buildings — in the
computer room, storage area — where the fire might
get out of control. During the initial period
of the fire, there will be additional protection.
However, in a 2000-degree fire, there are not
adequate facilities to overcome pressurization.
MR. SEMPIE: Smoke detectors are extremely impor-
tant to any smoke control system. The primary
thing to remember is to call the fire department
at the first smoke detector signal.
Smoke control systems are not designed to replace
fire ratings of walls. They are designed to help
the fire professionals perform the first two items
that they must perform. The fireman's first
function is to ensure that everyone has been
evacuated from the involved area.
His second function is to find the fire. With
the smoke control systems, the fire is being fed.
QUESTION: What about pressurization systems for
MR. SEMPLE: Absolutely not. It is not meant as
a substitute. Smoke control systems are intended
to be the first line of life- safety protection
because they are smoke actuated — thermally actu-
ated. Extinguishing devices are not fast enough.
MR. FUNG: Smoke control is only one of the whole
schemes of fire and smoke safety measures. How-
ever, it is significant since it concentrates on
life-safety more so than property protection.
It is the toxic products that kill, obstruct fire-
fighting and accumulate combustibles in areas
away from the fire.
Smoke control can eliminate the toxic smoke away
from the origin of fire. It can remove some of
the combustibles that cause flashover and can
increase visibility by removing smoke.
There are concerns about pressure differences due
to fire. One basic phenomenon of air pressure
in free expansion is that it attenuates very
rapidly. In fact, it attenuates as the inverse
of the distance.
1. Report No.
3. Recipient's Accession No.
I. Title and Subtitle
SEMINAR ON SMOKE CONTROL AS A PART OF BUILDING FIRE PROTECTION
MAY 3, 1977
5. Report Date
, January 24, 1978
7. Author(s) R Klinker,R Taylor, F Fung,B Semple,W Schmidt,
R Masters, W Hanbury
8. Performing Organization Rept.
No - NFPCA
9. Performing Organization Name and Address
FEDERAL FACILITIES DESIGN STANDARDS TASK GROUP
NATIONAL FIRE PREVENTION AND CONTROL ADMINISTRATION
DEPARTMENT OF COMMERCE
WASH DC 20230
10. Project/Task/Work Unit No.
11. Contract/Grant No.
12. Sponsoring Organization Name and Address
Jointly sponsored by the Task Committee 5.6 on Fire and
Smoke Control, American Society for Heating, Refrigeration,
and Airconditioning Engineers, Inc. (ASHRAE).
13. Type of Report & Period
15. Supplementary Notes
'The meeting was held to discuss the background, development, and status of smoke
movement and control technology as it pertains to building fire protection. This
was a jointly sponsored meeting with the Fire and Smoke Control Task Committee of
In recent years, considerable effort has been devoted to this subject. Other coun-
tries, as well as the US, have recognized the potential value of using smoke control
systems to assist in the safe evacuation of buildings while minimizing the adverse
effects of fires or other emergency situations endangering personnel and property.
Also, some design choices that have been implemented in new buildings have been
costly, but accomplished little.
17. Key Words and Document Analysis. 17a. Descriptors
17b. Identifiers/Open-Ended Terms
17c. COSATI Field/Group
18. Availability Statement
19. Security Class (This
20. Security Class (This
21. No. of Pages
FORM NTIS-35 (RES
10-73) ENDORSED BY ANSI AND UNESCO.
THIS FORM MAY BE REPRODUCED
U.S. DEPARTMENT OF COMMERCE
National Fira Prevention and Control Administration
Washington. O.C. 20230
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